BAGHDAD, Iraq (CNN) --A car bomb exploded Thursday outside the Jordanian Embassy in Baghdad, killing as many as 10 people, including five Iraqi guards, according to Iraqi and U.S. officials.

As many as 40 others were wounded in the blast, a U.S. military spokesman said.

CNN Correspondent Harris Whitbeck went to the scene of the blast and spoke Thursday with CNN's Heidi Collins.

WHITBECK: U.S. military forensics experts and other investigators are at the site of that bombing, trying to comb through the rubble to find out who carried out the attack.

The attack occurred around 10:30 [Thursday] morning local time. A powerful bomb exploded. Investigators believe it was packed in a minivan, which was parked in front of the diplomatic compound. The explosion was so big that -- so forceful that it brought down an outer wall of the embassy compound. It also destroyed several vehicles that were parked alongside that building.

... Five Iraqi policemen died. They were charged with safeguarding the embassy. We also understand -- according to wire reports -- that the Jordanian consul [Karim Shushan] was inside the compound when the attack happened, and he has been taken to a local hospital.

[There's] no word yet on who might be behind the attacks. But Gen. Ricardo Sanchez, who runs the U.S. military operation in Iraq, did say that this is the worst attack on a "soft target" since Baghdad fell to American forces April 9.

The U.S. has expressed its concerns that "foreign fighters" might be infiltrating into Iraq and that they might be trying to launch terrorist attacks against American interests and against the interests of those perceived to be supporters of the American effort in Iraq